Beyond cell shape: A novel role for the bacterial actin MreB in chemotaxis

项目摘要/摘要 细胞骨架对真核生物和细菌的正常生理都很重要。 细胞。然而，与真核细胞不同的是，人们为真核细胞做了很多工作 细胞骨架在细胞生理学中的作用的研究一直很少 致力于细菌细胞生物学的这方面工作。细胞骨架的破坏通常会导致 细胞形态改变和细胞死亡。细菌中的主要肌动蛋白同源物是MreB，它是 被认为是杆子形状的必需品。 这项工作的目标是移除微生物学的这个黑匣子，并确定 细胞骨架在微生物生理学中的作用。加深对MreB功能的认识 细菌生理学可以指导新的抗菌疗法的发展，如 也为细胞骨架的进化提供了洞察力。扰乱基本生理学 会使感染很难在体内扎根，从而使宿主的天然 为清除感染留出时间。这项提案将重点放在MreB在细胞中的作用 塑造调控、生长和趋化作用。 为了了解MREB是如何运作的，我们将使用 结合遗传、生物物理和显微技术来构建和 分析MreB突变体的丙氨酸扫描突变文库 原生等位基因。我们将分析这些突变对细胞多方面的影响 塑造和寻找抑制突变，从而失去细胞形状。我们将对这个图书馆进行筛选 以确定与MreB相互作用的结构域对趋化作用的影响 趋化性机械。 总之，这项研究将确定细菌细胞骨架在细菌中的作用 趋化性、细胞形状和生长。这些洞察力将为 开发可用于阻止或减缓感染的新疗法，使 宿主免疫系统清除感染的时间。此外，许多病原体使用 以鞭毛为基础的运动，以增加它们的毒力。了解更多关于趋化性如何 Works将使我们能够开发出可以抑制宿主运动的治疗方法，减少 感染。据我们所知，这项研究将是第一次对 了解MreB生物学的方法。

Project Summary/Abstract The cytoskeleton is important for proper physiology in both eukaryotic and bacterial cells. However, unlike eukaryotic cells, for which much work has been done to determine the role of the cytoskeleton in cellular physiology, there has been very little work on this aspect of bacterial cell biology. Disruption of the cytoskeleton often leads to cell shape changes and cell death. The major actin homolog in bacteria is MreB and it is thought to be essential for rod shape. The goal of this work is to remove this black box of microbiology and determine the role of the cytoskeleton in microbial physiology. A deeper understanding of MreB’s function and bacterial physiology can guide the development of novel antibacterial therapies, as well as provide insight into the evolution of the cytoskeleton. Disrupting basic physiology will make it difficult for infections to take hold in the body, giving the host’s natural defenses time to clear the infection. This proposal will focus on the role of MreB in cell shape regulation, growth, and chemotaxis. To understand how MreB functions we will take a systematic approach MreB using a combination of genetic, biophysical, and microscopy techniques to building and analyzing an alanine-scanning mutagenesis library of MreB mutants that have replaced the native allele. We will analyze the effect of these mutations on multiple aspects of cell shape and look for suppressor mutations to loss of cell shape. We will screen this library for the effects on chemotaxis to determine domains of MreB that interact with the chemotaxis machinery. All together this research will determine the role of the bacterial cytoskeleton in bacterial chemotaxis, cell shape, and growth. These insights will provide a starting point for the development of novel therapeutics that can be used to stop or slow infections, giving the host immune system time to clear the infection. Additionally, many pathogens use flagella-based motility to increase their virulence. Learning more about how chemotaxis works will enable us to develop therapies that can inhibit motility in the host, lessening infection. To the best of our knowledge, this study will be the first to take a systematic approach to understanding MreB biology.